Numerous writers in the field of education have noted the value of block play in the development of perceptual, motor and conceptual capabilities of children. Various buidling blocks have been described in the prior art which are used to amuse children, to provide them with a means to experiment with structures and forms and to provide them with an opportunity to excercise imagination and originality in creating new structural patterns such as shown in U.S. Pat. Nos. 3,787,996 3,303,604, 3,708,910, 2,319,914, 2,278,327 and 1,894,605.